Cannot Import .SVG File
To import an SVG file go to File > Import > Scalable Vector Graphics(SVG)



Make sure that the SVG file you are importing contains vectors (paths) Blender cannot import raster data or text directly form SVG files. In other words, the information on the SVG has to be traced. For a detailed explanation read this link

If the plugin is not enabled for any reason go to the User Preferences Window (press CtrlAltU and enable it there.

It is also possible that your file is importing successfully but is so small that is hard to see on the viewport. Check if the outliner shows one or more curve objects. 

If so, select one of the curves and press Numpad . to move the view to selected. Then you should be able to see the object.